$48 ANALYSIS OFTHE GALVANIC FILE. 



was a gradual diminution in the motion of the electro/copes, 

 and a change in the effects on the pile from the communica- 

 tion of its extremities with the ground. 



Unconnected g. Lastly, These chances could not be attributed to 



with heat, , _ * . . 



moisture, or those ot either heat or moisture, at least in my room, and as 



density of the influencing directly the pile; for the room remained nearly 



atmosphere. , J r , . . ,, , J 



at an equal temperature, and there were but small changes 



in my hygrometer, I also frequently observed the barome- 

 ter, and found no connexion between its variations and these 

 great changes in the strikings of the gold leaves. 

 Owing to elee- From the whole together of these observations, I could 

 attribute the variations in the electric phenomena of the 

 pile only to changes in the electric state of the ambient air ; 

 orthose in the effects of the communication with the ground, 

 to changeable differences between the electric stale of the lat- 

 ter and that of the air; an object on which we owe to Sig. 

 Volta showed, Volta a great and fundamental truth. This justly cele- 

 corftams th Crated experimental philosopher has made it evident, that 

 electtic fluid, oir possesses the electric Jiuid as well as all the bodies which 

 jt surrounds ; and on this principle he has founded the only 

 real explanation of the electric motions of free bodies, such 

 as the pairs of balls and the gold leaves of our electroscopes. 

 The electric Jiuid tends to an equilibrium among all bodies, 

 including the air, and there is a mutual attraction between 

 it and all of them, weak with conductors, but strong with 

 ftindards of nonconductor *', among which is air. The proportional quan» 

 plns& aijnus. tity of electric Jiuid, which is actually possessed by air, is the 

 standard of plus and minus in the electro/copes ; and the pro- 

 portional quantity of this Jiuid, which is actually possessed 

 by the ground, is the standard of plus and minus concerning 

 the differences in the electric state of insulated bodies com- 

 pared with its own : thet>e standards are sometimes similar, 

 but they are often different, J shall not enlarge here on this 

 beautiful theory, which I have fully explained in my works, 

 and demonstrated by direct experiments*; but applying it 

 Fffeotonthe to the pile, the immediate effects of the ambient air must 

 P Je * be, to give some electric Jiuid to its negative side, which has 



proportionally less than itself, and to take some from the 



* Idces sur fa Mitiorologie, published in London by Ejmsley in 1786 



apd 1767. 



positive 



